Oh, maybe it will happen in some occasion.. wow, if like that, this is serious problem...I should not marry western girl then, because it's said that 85% of women in western area (america) are Rh- and I have Rh+

It is the situation for the second baby if the vaccine (as much as I know it is something that prevents antibody production.) is not used after the birth of the first baby. The first child is not under danger.

It matters not how strait the gate
How charged with punishment the scroll
I am the Master of my fate
I am the Captain of my soul.

Probably as IgMs are produced first , which cannot cross human placent [ i don't know what happens about the other animals and how the babies are saved , does anybody know ???] So, even if the mothers body treates the baby as forign , it cannot make it die...
But please clear this one- why does ababy die when mother is Rh-ve and baby +ve???
Does the aglgutination formed in/near placenta / umbilical cord block nutient supply???
Please help...

What is the effect of this phenomenon on natural selection [ today natural selection would not occur,as there are medicine to help, but if it were to happen then...] ???

i don't know what happens about the other animals and how the babies are saved , does anybody know

Note that all the animal's blood systems are not the same.

So, even if the mothers body treates the baby as forign , it cannot make it die...

If it is the second baby, the mother can make the baby die. This is a the common result. But sometimes babies can born but there are some diseases at those babies.

At the first baby, there are no antibodies against Rh+, while birth, blood of the baby and the mother mixes and there are some antibodies produced, And those antibodies make the second baby die or born with some abnormalities. IgG can pass through placenta. Actually erythroblastosis fetalis can also be defined as the lysis of fetal RBCs by maternal IgGs .

It matters not how strait the gate
How charged with punishment the scroll
I am the Master of my fate
I am the Captain of my soul.

[ I THINK ].But the mixing ammounts of maternal and baby's blood are not enogh to make baby die even if all the fetal RBCs in that mixed blood blast . So, are you shure that these ammounts are large enough to make baby die...
Please help...

Ok, here is exactly what happens if the mother is Rh- and the baby Rh+:
1st baby: No problem, the baby is healthy. But at birth the blood of the mother is mixed with that of the baby. It really does not matter how much blood is mixed, ONE red blood cell is enough to enter the mother's circulatory sistem for her body to produce anti-Rh anitbodies.
2nd baby: If it is Rh+, than the antibodies created by the mother after she gave birth to the first baby will pass through the placenta and cause lysis...
Hope it is clear

"As a biologist, I firmly believe that when you're dead, you're dead. Except for what you live behind in history. That's the only afterlife" - J. Craig Venter